ORIGINAL ARTICLE Gu¨lek Mutlu Æ Latif Abbasog˘lu Semra Dog˘ru-Abbasog˘ lu Æ Seyhun Solakog˘lu Melih Bulut Morphologic changes and lipid peroxidation in renal tissues of young rats following intestinal ischemia-reperfusion Accepted: 10 January 2002 / Published online: 15 May 2002 Ó Springer-Verlag 2002 Abstract Intestinal ischemia-reperfusion (IIR) is a complex phenomenon causing local and remote tissue destruction, and even multiple-organ failure. To exam- ine the hypothesis that IIR affects renal function, 21- day-old male Sprague-Dawley rats underwent 45 min superior mesenteric artery occlusion and control rats were subjected to a sham laparotomy. After 2 and 24 h and 1 week of reperfusion, blood was sampled for urea and the kidneys were harvested for lipid peroxidation and histologic examination. Malondialdehyde (MDA) levels as an indicator of lipid peroxidation were signifi- cantly increased in renal tissue after 2 h of reperfusion, and this finding was in accordance with serum urea levels (SU) and endothelial injury. However, at 24 h of reperfusion MDA and SU had returned to normal. These data were supported by electron-microscopic studies suggesting reversibility of the changes. It is concluded that IIR leads to renal injury and that free radicals may be responsible for this injury. Keywords Ischemia-reperfusion Æ Kidney Æ Lipid peroxidation Æ Multiple organ failure Introduction Multiple-organ failure (MOF) after serious illness or injury is a major cause of death in the surgical intensive care unit [2, 10]. Despite intensive clinical and experi- mental studies, the exact pathophysiology of this syn- drome is still unclear. It has recently, been suggested that remote organ injuries are not due directly to exogenous factors such as bacteria or toxins, but are largely a consequence of the host’s own endogenously-produced mediators. Cytokines, endothelial-cell adhesion mole- cules, platelet activating factors, and free radicals are some mediators that involve and interact with each other in MOF syndrome [6, 12, 20]. Intestinal ischemia- reperfusion (IIR) induces remote organ injury, and has thus been used as a model for MOF syndrome [15, 18]. Several researchers have shown that hepatic and pul- monary dysfunction may occur after IIR [4, 11]. We investigated whether or not IIR induces damage to renal tissue in rats. Materials and methods Young male Sprague-Dawley rats weighing 60–80 g were used for all experiments. They were obtained from the Center for Experi- mental Medical Research and Application of Istanbul University, housed at 25 °C with 12-h light/dark cycles, and had free access to food and water until the experiment at the age of 21 days. Animals were divided into four groups (n = 10 each): the first group was subjected to a sham operation. All test groups were exposed to 45 min of superior mesenteric artery (SMA) occlusion and then 2 h, 24 h, and 1 week reperfusion, respectively. Animals were fasted overnight and anesthetized by intraperi- toneal ketamine (50 mg/kg). Anesthesia was maintained by i.m. injections of ketamine 10 mg/kg. The abdominal cavity was opened via a midline incision; the bowel was removed from the abdomen, the small intestine was reflected to the left, and individual group protocols were performed as follows. A sham procedure was per- formed in group 1 by dissecting the SMA and the bowel was re- placed into the abdomen. The wound was closed by 3/0 silk sutures. In groups, 2–4 the SMA was occluded with a microaneurysm clip, taking care not to occlude the superior mesenteric vein. The bowel was examined for absence of pulsations. After 45 min, reperfusion Pediatr Surg Int (2002) 18: 337–340 DOI 10.1007/s00383-002-0834-z G. Mutlu Æ L. Abbasog˘lu Æ M. Bulut Department of Pediatric Surgery, S¸ is¸li Children’s Hospital, S¸is¸li, Istanbul, Turkey S. Dog˘ru-Abbasog˘lu (&) Department of Biochemistry, Istanbul Faculty of Medicine, University of Istanbul, Istanbul, Turkey E-mail: abbasoglusl@hotmail.com Fax: +90-212-6311323/115 S. Solakog˘lu Department of Histology, Istanbul Faculty of Medicine, University of Istanbul, Istanbul, Turkey S. Dog˘ru-Abbasog˘lu University of Istanbul, Istanbul Faculty of Medicine, Department of Biochemistry, C¸ apa, 34390, Istanbul, Turkey